<ion-header>
  <ion-toolbar>
    <ion-buttons slot="secondary">
        <ion-button (click)="backClick()">   
            <ion-icon class="md-arrow-back"  ios="md-arrow-back"></ion-icon>
            返回
        </ion-button>
    </ion-buttons>
    <ion-buttons slot="primary">
      <ion-button color="danger">
        Edit
      </ion-button>
    </ion-buttons>
    <ion-title>标题</ion-title>
  </ion-toolbar>
</ion-header>

<ion-content>
  4t3543
</ion-content>